use 1.5 (to avoid minor warning)
diff --git a/org.eclipse.wtp.releng.versionchecker/META-INF/MANIFEST.MF b/org.eclipse.wtp.releng.versionchecker/META-INF/MANIFEST.MF
index 0927a0c..83b71ca 100644
--- a/org.eclipse.wtp.releng.versionchecker/META-INF/MANIFEST.MF
+++ b/org.eclipse.wtp.releng.versionchecker/META-INF/MANIFEST.MF
@@ -9,4 +9,4 @@
 Eclipse-LazyStart: true
 Export-Package: org.eclipse.wtp.releng.tools.versionchecker
 Bundle-Vendor: %Bundle-Vendor.0
-Bundle-RequiredExecutionEnvironment: J2SE-1.4
+Bundle-RequiredExecutionEnvironment: J2SE-1.5